1. The Field of the Invention
The present invention relates to systems and components for stabilizing adjacent vertebrae of the spine or other adjacent bones and, more specifically, it relates to radiolucent stabilizing rods and screw systems used in stabilizing adjacent vertebrae.
2. The Relevant Technology
Spinal stabilizing systems are commonly used for adjusting or stabilizing adjacent vertebrae of a spine. A typical spinal stabilizing system includes bone screws that secure to the vertebrae and stabilizing rods that extend between the bone screws. For example, in one conventional procedure a first bone screw is screwed into a first vertebra while a second bone screw is screwed into an adjacent second vertebra. A stabilizing rod is then secured between the bone screws so as to fix the adjacent vertebrae relative to each other. Bone screws can be positioned on each side of each vertebra and can be positioned in any number of consecutive vertebrae with one or more stabilizing rods extending between the different bone screws.
A conventional bone screw comprises a threaded shaft having a collar mounted on the end thereof. The threaded shaft is screwed into the vertebrae and the stabilizing rod is received within the collar and secured therein. To be strong enough to handle the stresses placed upon them, the bone screws and stabilizing rods are typically made of titanium or some other high strength, biocompatible metal. As a result of being made of metal, a physician is able to view the bone screws and stabilizing rods using X-ray photographs during and after implantation.
However, the metal bone screws and stabilizing rods also block the X-rays and prevent them from passing through the body. As a result, the metal bone screws and stabilizing rods obscure adjacent bone and other X-ray viewable internal structures surrounding the area, thereby preventing the physician from viewing those structures on an X-ray photograph. This screening can limit a physician's ability to ensure proper placement/orientation of the bone screws and stabilizing rods relative to the surrounding bone structure. Such screening can also hamper the diagnoses and treatment of problems that arise near the location of the bone screws and stabilizing rods after the bone screws and stabilizing rods have been implanted.
Accordingly, what is needed are spinal stabilizing systems, including stabilizing rods, that overcome some or all of the above disadvantages.